[1] Univ South Eastern Norway, Fac Hlth & Social Sci, Dept Nursing & Hlth Sci, Drammen, Norway
[2] Univ Oslo, Inst Hlth & Soc, Dept Nursing Sci, Oslo, Norway
[3] Oslo Univ Hosp, Dept Res & Dev, Div Emergencies & Crit Care, Oslo, Norway
[4] Univ Oslo, Fac Med, Dept Biostat, Oslo, Norway
[5] Oslo Univ Hosp, Dept Resp Med, Oslo, Norway
[6] Univ Oslo, Inst Clin Med, Fac Med, Oslo, Norway
[7] Western Norway Univ Appl Sci, Dept Hlth & Caring Sci, Haugesund, Norway
[8] Univ South Eastern Norway, Fac Hlth & Social Sci, Dept Nursing & Hlth Sci, Gronland 58, N-3045 Drammen, Norway